• 수산해양교육연구
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• 제27권1호
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• pp.41-48
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• 2015

Juvenile banded catfish(Pseudobagurus fulvidraco, mean length $10.4{\pm}0.37cm$ and mean weight $14.5{\pm}0.46g$) were exposed to several nitrite(${NO_2}^-$) concentrations for 96h at pH levels of $6.18{\pm}0.54$, $6.5{\pm}0.30$ and $7.07{\pm}0.22$. The result showed that cumulative mortalities of fish to ${NO_2}^-$ levels of 12.4, 19.8, 33.9 and 53.6 mg/L at pH levels of $6.18{\pm}0.54$ were 20, 25, 40 and 85%, respectively. At pH $6.5{\pm}0.54$, mortalities to ${NO_2}^-$ 22.4, 36.4, 45.3 and 63.2 mg/L were 25, 35, 50 and 100%, respectively. At pH $7.07{\pm}0.22$, mortalities to ${NO_2}^-$ 25.5, 45.7, 56.3 and 66.4 mg/L were 0, 55, 70 and 100%, respectively. The 96h-$LC_{50}$(median lethal concentration, $LC_{50}$) of fish to several ${NO_2}^-$ concentrations at pH levels of $6.18{\pm}0.54$, $6.5{\pm}0.30$ and $7.07{\pm}0.22$ were assessed in these experiments. 96h-$LC_{50}$ at pH levels of $6.18{\pm}0.54$, $6.5{\pm}0.30$ and $7.07{\pm}0.22$ were 32.68, 40.49 and 45.85 mg/L, respectively. It indicated that acute toxicity of ${NO_2}^-$ to juvenile banded catfish increased with low levels of pH and lengthening of exposure time to ${NO_2}^-$. In particular, smaller fish(mean weight $14.5{\pm}0.46g$) were more sensitive to ${NO_2}^-$ than larger fish(mean weight $81.7{\pm}1.42g$; not published). The 96h-$LC_{50}$ of juvenile banded catfish to ${NO_2}^-$ would be primary guideline for water quality management in the intensive culture system such as RAS and BFT.

• 전기전자학회논문지
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• 제22권2호
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• pp.495-498
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• 2018

본 논문에서는 의료 및 산업용 X-선 발생장치의 선량평가를 위한 면적선량계(DAP)의 시스템을 제안한다. 제안하는 시스템은 Ion-Chamber를 이용한 면적선량 측정기술을 기반으로 진단용 X-선 장치에 의해 발생된 피폭선량을 명확히 측정할 수 있다. 면적선량계의 하드웨어부는 공기 중에서 X-선에 의해 전리되는 전하의 양을 측정한다. 미소 전류를 통한 누적선량 측정을 위한 고속 처리 알고리즘부는 입력 손실 없이 낮은 구현비용(전력)으로 X-선에 의해 전리되는 전하의 양을 측정한다. X-선 발생장치의 동작에 동기화된 유무선 송수신 프로토콜부는 통신 속도를 향상시킨다. 연동 및 에이징을 위한 PC 기반 제어 프로그램부는 실시간으로 발생된 X-선량을 측정하여 PC용 GUI를 통해 측정 그래프 및 수치 모니터링이 가능하도록 한다. 제안된 시스템의 성능을 공인시험기관에서 평가한 결과, 각각의 에너지 대역(30, 60, 100, 150kV)에서 면적선량계에 측정되는 값이 선형적으로 증가됨을 확인할 수가 있었다. 또한 4등분한 지점에서 측정기의 지시치에 대한 표준편차가 ${\pm}1.25%$를 나타내어서 면적선량계가 위치에 관계없이 균일한 측정값을 나타냄을 확인하였다. 한편, ${\pm}4.2%$의 불확도가 측정되어서 국제 표준인 ${\pm}15%$ 이하에서 정상동작 됨이 확인되었다.

• 대한한방내과학회지
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• 제19권1호
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• pp.385-408
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• 1998

Pyeongpaesan (平肺散) has been used in Korea for many centuries as a treatment for respiratory disease. The effect of Pyeongpaesan (平肺散) on tracheal smooth muscle is not known. The purpose of the present study is to determine the effect of Pyeongpaesan (平肺散) on histamine and acetylcholine induced tracheal smooth muscle contraction in rats and guinea pigs. Guinea pig (500 g, male) and Sprague Dawley rats (200 g, male) were killed by $CO_2$ exposure and a segment (8-10 mm) of the thoracic trachea from each rat and guinea pig was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 0.5 g loading tension. The dose of histamine (His) and acetylcholine (Ach) which evoked 50% of maximal response ($ED_{50}$) was obtained from cumulative dose response curves for histamine and acetylcholine $(10^{-7}{\sim}10^{-4}M)$. Contractions evoked by His $(ED_{50})$ and Ach $(ED_{50})$ were inhibited significantly by Pyeongpaesan (平肺散). In guinea pig tracheal smooth muscle, the mean percent inhibition of acetylcholine induced contraction was 13.5% (p<0.05) after $10{\mu}l/ml$ Pyeongpaesan (平肺散), $64.6\(p<0.01)\;after\;30{\mu}l/ml$ Pyeongpaesan (平肺散), and $92.8\(p<0.01)\;after\;100{\mu}l/ml$ Pyeongpaesan (平肺散). In rat tracheal smooth muscle, the mean percent inhibition of acetylcholine induced contraction was $60.9\(p<0.01)\;after\;30{\mu}l/ml$ Pyeongpaesan (平肺散), and $91.2\(p<0.01)\;after\;100{\mu}l/ml$ Pyeongpaesan (平肺散). Also, in guinea pig tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was $104.8\(p<0.01)\;after\;30{\mu}l/ml$ Pyeongpaesan (平肺散) and $142.3\(p<0.01)\;after\;100{\mu}l/ml$ Pyeongpaesan (平肺散). In rat tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was $63.7\(p<0.01)\;after\;30{\mu}l/ml$ Pyeongpaesan (平肺散), and $107.5\(p<0.01)\;after\;100{\mu}l/ml$ Pyeongpaesan (平肺散). Propranolol $(10^{-7}M)$ slightly but significantly attenuated the inhibitory effects of Pyeongpaesan (平肺散). Following treatment with propranolol, the mean percent inhibition caused by $100{\mu}l/ml$ Pyeongpaesan (平肺散) fell to 15.7% (p<0.05) in guinea pig induced by acetylcholine contraction and the mean percent inhibition caused by $100{\mu}l/ml$ Pyeongpaesan (平肺散) fell to 22.3% (p<0.05) in guinea pig induced by histamine contraction and by $100{\mu}l/ml$ Pyeongpaesan (平肺散) fell to 28.7% (p<0.01) in rat induced by histamine contraction. Indomethacin and methylene blue $(10^{-7}\;M)$ did not significantly alter the inhibitory effect of Pyeongpaesan (平肺散). Also, I could find the effects of Pyeongpaesan (平肺散) and Pyeongpaesanga (平肺散加) morphine on the tracheal smooth muscle in guinea pig and rat did not change significantly. These results indicate that Pyeongpaesan. (平肺散) can relax histamine and acetylcholine-induced contraction of guinea pig and rat tracheal smooth muscle, and that this inhibition involves sympathetic effects and the release of cyclooxygenase products.

• 동의생리병리학회지
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• 제17권2호
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• pp.493-498
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• 2003

Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamchotang have been used in Oriental Medicine for many centuries as a treatment for various disease. The purpose of the present study is to determine the effect of Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamchotang on narepinephrine(NE) induced contraction of isolated rabbit femoral artery. Rabbits (2.0kg, female) were killed by CO₂ exposure and a segment (8-10mm) of the aortic ring from each rabbit was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 1.5g loading tension. The dose of NE which evoked 50% of maximal response (ED/sub 50/) was obtained from cumulative dose response curves for NE (10/sup -7/～10/sup -4/M). Contractions evoked by NE (ED/sub 50/) were inhibited significantly by Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamcho-tang. The mean percent inhibition of NE induced contraction was 83.9% (p<0.01) after 150㎕/㎖ Paeoniae Radix, 101.1 %(p<0.01) after 150 ㎕/㎖, Glycyrrhizae Radix and 107.3%(p<0.01) after 150㎕/㎖ Jakyakgamcho-tang, Indomethacin slightly but significantly attenuated the inhibitory effects of Paeoniae Radix. Following treatment with indomethacin, the mean percent inhibition caused by 150㎕/㎖ Paeoniae Radix fell to 16.4% in femoral artery induced by NE contraction. Propranolol, ODQ, and L-NNA did not significantly alter the inhibitory effect of Paeoniae Radix. ODQ slightly but significantly attenuated the inhibitory effects of Glycyrrhizae Radix. Following treatment with ODQ, the mean percent inhibition caused by 150㎕/㎖ Glycyrrhizae Radix fell to 13.0% in femoral artery induced by NE contraction. Propranolol, indomethacin and L-NNA did not significantly alter the inhibitory effect of Glycyrrhizae Radix. L-NNA slightly but significantly attenuated the inhibitory effects of Jakyakgamchotang. Following treatment with L-NNA, the mean percent inhibition caused by 150㎕/㎖ Jakyakgamchotang fell to 13.8% in femoral artery induced by NE contraction. Propranolol, ODQ and indomethacin did not significantly alter the inhibitory effect of Jakyakgamcho-tang. These results indicate that Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamcho-tang can relax NE induced contraction of the isolated rabbit femoral artery, and that this inhibition related to nitric oxide.

• 생약학회지
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• 제46권1호
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• pp.44-51
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• 2015

The objective of this study is to characterize a toxicity of Polygalae Radix (PR) in F344 rats and to find a dose levels for the 13 weeks toxicity study. PR is well known as medicinal herb in many Asian countries for treatment of expectorant, tonic, tranquillizer, antipsychotic agent and functional diet for improving memory. However, there is insufficient background information on toxicological evaluation of PR extract to support its safe use. Therefore, we conducted toxicological evaluation of this drug in compliance with OECD and KFDA guideline in this study. The extract of PR was administered orally to F344 rats at dose levels of 0, 500, 1000, 2000, 3500 and 5000 mg/kg/day for 2 weeks. Each group was composed to five male and five female rats. In the result, there were no treatment PR-related adverse changes in food consumption, hematology, clinical chemistry, urinalysis, gross finding at necropsy, organ weight examination. Four males at 5000 mg/kg/day were found dead during the treatment period. These animals showed salivation. The cause of death is still under investigation. The animals treated at 500, 1000, 2000, 3500 and 5000 mg/kg/day showed salivation and all animals at 5000 mg/kg/day exhibited lower body weight and cumulative weight gain in compared to those of control animals. Therefore, we recommend that a dose group of 3500 mg/kg/day is a highest treatment group in 13-week exposure study.

• 한국환경농학회지
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• 제35권4호
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• pp.241-246
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• 2016

BACKGROUND: Recently, the widespread distribution of pesticides in the hive has been of concern about pesticide exposure on honeybee (Apis mellifera L.) health. Larval toxicity was adapted to assess the synergistic and antagonistic interaction of cumulative mortality to the honeybee larvae of the four most common pesticides detected in pollen. METHODS AND RESULTS: Acetamiprid($3.0{\mu}l/L$), chlorothalonil ($803.0{\mu}l/L$), coumaphos ($128.0{\mu}l/L$), and tau-fluvalinate ($123.0{\mu}l/L$) were tested in combination; binary, ternary and four component mixture. Larvae were exposed to four pesticides mixed in diet at the average levels detected in pollen. As a result, synthetic toxicity was observed in the binary mixture of acetamiprid with coumaphos. The binary and ternary component mixtures of tested pesticides have mostly demonstrated additive effect in larval bees. The significant antagonistic effects were found in four parings of mixtures including chlorothalonil added to acetamiprid/tau-fluvalinate or acetamiprid/coumaphos/tau-fluvalinate, and tau-fluvalinate added to acetamiprid/chlorothalonil or acetamiprid/coumaphos/chlorothalonil. CONCLUSION: Interactions between combinations of four pesticides showed mostly additive or antagonistic effects in larval bees. Therefore, predicting the larval mortality of pesticides mixtures on the basis of the results of single pesticide may actually overestimate the risk. We suggest that pesticide mixture in pollen be evaluated by adding their toxicity together for complete data on interactions.

• Journal of Preventive Medicine and Public Health
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• 제17권1호
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• pp.5-24
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• 1984

There has been an immense need for elaborate studies on the complications and the neuological sequelae generated by acute carbon monoxide (CO) poisoning which is highly prevalent in Korea due to widespread adoption of the anthracite coal briquette as domestic fuel for heating and for cooking. For this epidemiological study, a total of 444 subjects who received hospital emergency care for acute CO poisoning during the period of March 1982 to February 1983 were randomly selected from the emergency patients's lists of 13 general hospitals in Seoul area. Informations on the neurological sequelae were elucidated by means of home visiting with prearranged questionnaire consisting questions and concise neurological examination. The findings obtained were summarized as follows; 1. The complications were found in 18% of the surveyed and acute decubitus was comprised 67.5% of the complications. 2. The total cumulative incidence of the neurological sequelae was 41.2 per 100 patients and the absolute incidence rate regardless of the duration after poisoning was 40.8%. 3. The incidence of the neurological sequelae was higher in the older age than in the younger and also higher in female than in male. Twice higher incidence was observed in the admitted patients than in the non-admitted patients and the incidence became higher in proportion to the duration of CO exposure, coma and admission. The poorer the consciousness level of patients found, at emergency room and at discharge, the higher the incidence. The incidence of the neurological sequelae by emergency care was higher in hyperbaric oxygen therapy group(51.9%) than in 100% $O_2$ group(38.0%) 4. A total of five variables significantly associated with the occurrence of the neurological sequelae were selected by the stepwise discriminant analysis. The variables were following course of emergency care, age, consciousness level at discharge, admission duration, and consciousness level at emergency room in their sequence of discriminant power. Eight variables were selected as those associated with the degree of the neurological sequelae through the stepwise multiple regression analysis. Of these variables, the acute decubitus alone explained 21.1% of the total variation ana all the eight variables could explain 36.5% of the same. The remaining seven variables listed in the order of their relative importance were: age, consciousness level at discharge, admission duration, coma duration and consciousness level at emergency room. 5. It was postulated that unexpectedly high incidence of the neurological sequelae of the CO poisoning in this epidemiological study was mainly due to the inadequate emergency care and the lack of efficient and sophisticated treatment measure. In the effort to minimize the incidence of grave neurological sequelae of acute CO poisoning, new guidelines for the emergency care and treatment should be pursued with efficient ways.

• 한국도로학회논문집
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• 제10권4호
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• pp.151-159
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• 2008

차선의 밝기를 나타내는 반사성능은 교통량, 도색 후 경과시간, 차선재료, 색상 등에 따라 지역별로 차이가 발생한다. 본 연구에서는 고속도로에서 조사된 차선 성능의 자료를 바탕으로 교통량과 차선의 공용수명을 독립변수로 하고 차선의 성능을 종속변수로 하는 회귀식을 산정하였다. 전국의 고속도로를 대상으로 모바일 차선반사 성능 차량을 사용하여 $2005{\sim}2006$년의 2년동안 3개월 간격으로 차선의 성능을 추적 조사하였다. 축적된 DB에는 차선의 성능뿐 아니라 차선의 재료, 색상, 기하구조, 교통량, 도색시기 등이 포함되어 있다. 본 연구에서 추적 조사된 차선성능을 기초로하여 다양한 환경에서의 차선재료의 성능을 비교 분석하여 여러 인자에 의한 차선성능 곡선을 도출하였다. 차선성능 곡선을 통해 지역별 교통량과 도색 이후의 시간의 경과에 따른 차선의 성능을 예측할 수 있었다. 선형함수, 로그함수, 지수함수, 음지수함수 등을 이용하여 차선의 성능을 나타내는 회귀식과 변동을 추정한 후, 결정계수가 가장 높고, 현장측정치와 가장 유사한 모형을 차선의 성능 예측모형으로 결정하였다. 현장조사 결과와의 검증결과, 차선성능 예측 모델은 90% 신뢰도에서 유의함을 볼 수 있었고, 특히 누적 교통량의 증가에 따라 현장 데이터와 높은 연관성을 보여주었다. 따라서 본 방법론에 의한 차선수명 예측 모델을 통해 차선의 공용수명과 잔존수명을 예측하여 도색시기를 결정할 수 있다.

• Korean Journal of Acupuncture
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• 제18권1호
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• pp.157-164
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• 2001

Radix Asteris has been used in Korea for many centuries as a treatment for respiratory disease. The effect of Radix Asteris on tracheal smooth muscle is not known. The purpose of the present study is to determine the effect of Radix Asteris on histamine induced tracheal smooth muscle contraction in rats and guinea pigs. Guinea pig(500g, male) and Sprague Dawley rats (250g, male) were killed by $CO_2$ exposure and a segment (8-10mm) of the thoracic trachea from each rat and guinea pig was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 0.5g loading tension. The dose of histamine (His) which evoked 50% of maximal response ($ED_{50}$) was obtained from cumulative dose response curves for histamine $(10^{-7}{\sim}10^{-4}M)$. Contractions evoked by His ($ED_{50}$) were inhibited significantly by Radix Asteris. In guinea pig tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was 120.5% (p<0.01) after $100{\mu}l/ml$ Radix Asteris. In rat tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was 135.4% (p<0.01) after $100{\mu}l/ml$ Radix Asteris. Propranolol $(10^{-7}M)$ slightly but significantly attenuated the inhibitory effects of Radix Asteris. Following treatment with propranolol, the mean percent inhibition caused by $100{\mu}l/ml$ Radix Asteris fell to 44.6% in guinea pig induced by histamine contraction and by $100{\mu}l/ml$ Radix Asteris fell to 18.7% (p<0.05) in rat induced by histamine contraction. Indomethacin and methylene blue$(10^{-7}M)$ did not significantly alter the inhibitory effect of Radix Asteris. These results indicate that Radix Asteris can relax histamine induced contraction of guinea pig and rat tracheal smooth muscle, and that this inhibition involves sympathetic effects.

• 농약과학회지
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• 제7권2호
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• pp.131-138
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• 2003

수도용 농약의 미꾸리에 대한 영향 평가를 위한 야외포장 시험방법을 설정하기 위하여 미꾸리가 서식하고 있는 실제 포장에서 수도용 농약인 아이비 엽제 (17%), 다수진 엽제 (3%), 그리고 부타크로르 입제 (5%)의 미꾸리에 대한 영향을 시험하였다. 시험 케이지는 미꾸리의 스트레스를 최소화 할 수 있는 아래 윗면이 트인 사각 스테인레스 케이지가 적당하였고, 수온 유지와 해적으로부터 보호하기 위한 차광망과 방조 망의 사용이 필수적이었다. 아이비 입제, 다이아지논 입제 그리고 부타크로르 입제에 대한 7일간 미꾸리 누적 치사율은 각각 10, 55, 22% 이었다. 특히 약제 처리 2일후 논물 중 평균 농약잔류량은 각각 1.67, 0.22, 0.26 mg/L이었으며, 치사율은 각각 7, 50, 17%로 나타났다. 이는 실내 급성독성시험을 통한 각각의 급성독성 시험결과와 유사하였다.